14 init_ rlslattice2

Purpose

Creates and initializes the variables required for the RLS-Lattice Joint Process Estimator using the a priori estimation errors with error feedback.

Syntax

[ff,bb,cf,b,d,y,e,kf,kb,c] = init_rlslattice2(L)
[ff,bb,cf,b,d,y,e,kf,kb,c] =
init_rlslattice2(L,ff0,bb0,kf0,kb0,c0,cf0,b0,d0)

Description

Figure 5.20: Block diagram of the RLSLATTICE-2 adaptive Joint Process Estimator.

The variables of the RLS LATTICE-2 are summarized below (see Fig. 5.20).

Input Parameters [Size]:: 
  L   : Linear combiner length
  ff0 : autocorrelation of forward prediction error [Lx1]
  bb0 : autocorrelation of backward prediction error [Lx1]
  kf0 : forward lattice coefficients [Lx1]
  kb0 : backward lattice coefficients [Lx1]
  c0  : linear combiner coefficients [Lx1]
  cf0 : conversion factor [Lx1]
  b0  : vector of backward a priori estimation error [Lx1]
  d0  : desired response [1x1]
Output parameters [Default]::
  ff  : initialized ff [.001*ones(L,1)]
  bb  : initialized bb [.001*ones(L,1)]
  cf  : conversion factor [ones]
  b   : vector of a priori backward estimation error [zeros]
  d   : desired output [rand]
  y   : Linear combiner output [c' * b]
  e   : Linear combiner error [d-y]
  kf  : forward lattice coefficients [zeros]
  kb  : backward lattice coefficients [zeros]
  c   : linear combiner coefficients [zeros]

Example

L  = 5;               % Number of lattice stages 
ff = 0.001*ones(L,1); % autocorr. of forward prediction error
bb = 0.001*ones(L,1); % autocorr. of backward prediction error
kf = zeros(L,1);      % forward lattice coefficients
kb = zeros(L,1);      % backward lattice coefficients
c  = zeros(L,1);      % Linear combiner coefficients
cf = zeros(L,1);      % conversion factor
b  = zeros(L,1);      % backward prediction error 
d  = .22;             % initial desired sample

% Create and initialize an RLS lattice-2 filter
[ff,bb,cf,b,d,y,e,kf,kb,c] = 
           init_rlslattice2(L,ff0,bb0,kf0,kb0,c0,cf0,b0,d0)

Remarks

• Supports both real and complex signals and filters.
• Use input parameters 2 through 9 to initialize the algorithm storage. This is helpful when the adaptation process is required to start from a known operation point calculated off-line or from previous simulations.

See Also

ASPTRLSLATTICE2.